Langcache: Usability changes

[cmilesb]

DOC-5528 - Changes from meeting with Jen on 7/31:

• Send users to API/SDK examples instead of API reference in use langcache
• Add anchor to Getting started on the top of the Langcache overview page
• Move link in Use Langcache to API/SDK up so it’s immediately visible

[github-actions]

Staging links:
https://redis.io/docs/staging/DOC-5528/develop/ai/langcache/
https://redis.io/docs/staging/DOC-5528/operate/rc/langcache/use-langcache.md

[dwdougherty]

LGTM.

[andy-stark-redis]

LGTM too. Only observation, really, is that you can override the footer link for each example now in the default tab (ie, cURL in this case). You could add a link to the API ref page there, maybe? This would show the footer for the other languages, but maybe showing the quickstart link for them isn't that much of a problem?

Anyway, the current solution is fine - just throwing in an idea :-)